Ysarex wrote:
That's wrong. One example of why that's wrong is the focus systems in the cameras. Mirrorless cameras are implementing their auto-focus systems directly on the sensor. This has the advantage of unparalleled accuracy. That's a technology going into mirrorless that you can't apply to a DSLR.
It can be applied, they just don't want to. During live view when the mirror is up there is no reason why the autofocus technology used in the mirrorless can not be applied. There is nothing on the way and the back screen will act as an EVF.
Ysarex wrote:
The wide angle lens design compromise in force for all DSLRs results in larger heavier lenses and lenses with uncorrectable distortion. A perfect example of this difference can be seen in comparing a Hasselblad SWC with a Zeiss 40mm Distagon for the Hasselblad SLR. The fact that both exist testifies to the existence of the issue.
No there is not. Some designs can easily cope with the requirements of wide angle lens on DSLR. Performance compromise within physical boundaries is a manufacturers decision.
Ysarex wrote:
More rubbish. The lens mount to sensor distance is a critical factor in lens design and performance.
No it is not. Any reasonable mount to sensor distance can be accommodated by the adjusting the focusand if out of range, designing a lens element for that distance. That is why extension tubes & bellows work.[/quote]
Ysarex wrote:
Wide angle lenses on DSLRs are performance compromised by being forced farther away from the sensor in order to provide room for the mirror. This is common knowledge. Here's a wiki article:
https://en.wikipedia.org/wiki/Angénieux_retrofocus and a paragraph from the article: "
In still photography, a single-lens reflex camera requires a space for the reflex mirror, imposing a limit on the use of wide-angle lenses of symmetric designs. The retrofocus lens addressed this situation by increasing the distance between the rear element and the focal plane, thus making wider-angle lenses usable while retaining normal viewing and focusing. Unless the reflex mirror were locked in the "up" position, blacking out the viewfinder, the rearmost element(s) of a non-retrofocus (symmetric wide-angle) lens would interfere with the movement of the mirror as it flipped up and down during exposure."
br Wide angle lenses on DSLRs are performance com... (
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You really have your own ideas when you read something. Read it again, slower and without bias.
Let me clarify things for you;
1. The telephoto lens configuration combines positive and negative lens groups with the positive at the front, so as to reduce the back focal distance of the lens.
2. This is for practical, not for optical reasons
meaning there is no IQ problem about changing/controlling the distance to create an optically good lens 3. The inverted telephoto configuration by is the same design but employs one or more negative lens groups to increase the back focal distance.
A. A single-lens reflex camera requires a space for the reflex mirror, imposing a
limit on symmetric design wide angle lens.
B.
The inverted telephoto configuration lens addresses this situation by increasing the distance between the rear element and the focal plane
C.The Angénieux retrofocus lens is a wide-angle lens design that use an inverted telephoto configuration.
The Angénieux retrofocus lens & other similar design allows manufacture of wide angle lenses in SLR & similar cameras with long back focal distance. It does not have the compromise you are talking about.